Crankshaft lapping machine



July 11,1939. w. H. wooo 2,166,084

CRANKSHAFT LAPPING MACHINE Filed 001;. 3, 1938 5 Sheets-Sheet 2 July 11, 1939. w. H. WOOD 2,166,084

CRANKSHAFT LAPPING MACHINE Filed Oct. 5, 1938 5 Sheets-Sheet 5 F 5 230 WALLACE H.

July 11, 1939. I w, WQQD 2,166,084

CRANKSHAFT LAPPING MACHINE Filed on. s, 1938 5 Sheets-Sheet 5 UNITED STATES ATENT OFFICE CRANKSHAFT LAPPING MACHINE Wallace H. Wood, Worcester, Mass, assignor to Norton Company, Worcester, Mass, a corporation of Massachusetts Application October 3, 1938, Serial No. 233,003

20 Claims.

The invention relates to abrading machines, and more particularly to a crankshaft lapping machine.

One object of the invention is to provide a control valve, showing the valve in its third position on its rearward movement;

Fig. 6 is a similar vertical sectional view, showing the control valve in its rearward or rightsimple and thoroughly practical lapping machine hand position; for simultaneously lapping or polishing a plu- Fig. '7 is a similar vertical sectional view, showrality of crankpins and main bearings on a cranking the control valve in its second position durshaft. A further object of the invention is to ing its forward movement; provide a crankshaft lapping machine in which 8 is a similar horizontal sectional view, all .of the crankpins and main bearings may be showing the control valve in its third position simultaneously lapped. Another object of the during its forward movement; invention is to provide a crankshaft lapping ma- Fig. 9 s a fragmentary Sectional V W hOWiHE chine for simultaneously lapping the crankpins the rear end of the control valve and latch mechand bearings of a crankshaft in which a pluanism in elevation; rality of lapping arms are hydraulically operated. Fig. 10 is a right-hand end elevation of the A further object of the invention is to provide a headstock mechanism, on an enlarged scale; crankshaft lapping machine in which all of the Fig. 11 is a fragmentary sectional view taken bearing and crankpin lapping arms are mounted eppreXimetely en the line l Of ShOW- on a movable frame which is movable to and 111:; the lapping arm Clamping mechanism; from an operating position by ahydraulically op- Fig. 12 is a fragmentary end elevation of a erated mechanism. A further object of the incrank pp arm and its pp r and clampvention is to provide a hydraulically operated ing mechanism; and clamping mechanism for clamping the lapping Fig. 13 is a fragmentary cross sectional view, arms in an indexed position during the loading on an enlarge seh1e,t&keh epprOXimetely 0n the operation. line l3l3 of Fig. 11.

A further object of the invention is to provide A C a s a t pp machine as be n i lusa hydraulically operated footstock for aiding in trated in the drawings comprising a base 20 supporting the work. A further object of the wh pp r a on i d n l y recinreeeble invention is to provide a single control valve for work supp table 2L Table Ways are prointerlocking the various hydraulic mechanisms vided between the base 25 and the table 2| which of the machine. Another object of th invenin the preferred form are of an anti-friction type. tion is to provide a plurality of stops or latches The hElse 29 is provided with e plate 25 W ich s to restrict the movement of the control valve so fiXed the base 29 and is proVided at its dge as t i t l k th various hydraulically portions with grooves 27 and 28 which serve as erated mechanisms of the machine so that all ihhel raceway-s for it P Of Space OWS 0f antimust be operated in a definite and predetermined frietieh balls 29 and respectively A Cage is cycle. provided between the races to space the balls 29 The invention accordingly consists in the feaand 3910hgitudiha1ly, as desired. s C st tures of construction, combinations of elements, Dion forms an anti-friction y whereby the table and arrangements of parts as 111 b exemplified 2! together with a headstock 22 and a footstock 23 40 in the structure to be hereinafter described, and may be readily leeipleeated during the app g the scope of the application of which will be in- Operationdicated in the following claims. Head-stock In t p y n drawings in w h is The headstock 22 is provided with a rotatable shown one of various possible embodiments of pindle 33 which is supported in bearings (not the mechanical features Of this invention, hown) The headstock spindle may be 1'0- Fi 1 s a front elevation of the imprOVed tated from any suitable source of power, such as Crankshaft app machine; an overhead, belt drive, or a self-contained elec- Fig- 2 s a d eleValJiOh, 011 a enlarged tric motor. In the preferred construction, an of th i p ved cranks a t a p ma hine; electric motor 34 is mounted in the base at of Fi 3 is a i r m illustration of the ythe machine. The motor 34 is provided with a draul e actua mechanism and p p g togethdriving pulley 35 which is connected by multiple or with the control Valv and th interlocking V-belts 36 with a pulley 3? on the headstock 22. stop or latch mechanism therefor; The headstock construction has not been illus- Fig. 4 is a horizontal sectional View through trated in detail in the present application since the hydraulic control valve, showing the valve this headstock is not considered to be a part of in its second position during its rearward movethe present invention and, furthermore, is identiment; cal with that shown in the prior United States Fig. 5 is a vertical sectional view through the Patent No. 2,092,734 dated September 7, 1937,

to which reference may be had for details of disclosure not found herein.

Table reciprocation In the lapping of crankpins and main bearings of an automotive crankshaft or the cams and main bearings of an automotive camshaft, it is desirable to provide a relative reciprocatory movement between the crankshaft or camshaft being lapped and the lapping or abrading element to prevent production of abrasive grain markings on the pins and bearings of the crankshaft. In the present case, the work table 2| is arranged for a longitudinal reciprocatory movement which is preferably accomplished by a translation of the rotary motion of the headstock spindle 33 into a reciprocatory movement of the table 2 l. The specific mechanism for reciprocating the table 2| has not been illustrated in the present case, since this mechanism is identical with that shown in the prior United States Patent No. 2,092,734 dated September '7, 1937, to which reference may be had for details of the table reciprocating mechanism not found herein.

Footstoclc The other end of the crankshaft 24 is supported by the footstock 23 which is provided with a footstock center The center 5i is carried by a rotatable spindle 52 which is journalled in bearings 53 and 5% within a hollow slidably mounted sleeve 55. The sleeve 55 is slidably keyed by means of a key 55 within an aperture in the footstock frame.

A fluid pressure actuated mechanism is provided for moving the footstock center 5i rapidly to and from an operative position to support one end of a crankshaft 2 3 within the machine. This mechanism comprises a fluid pressure cylinder 58 having a slidably mounted piston 59 contained there in. The piston 59 is connected to one end of a piston rod 68 which is connected to a pin 6 l. The central portion of the pin 6! is slabbed off on opposite sides so as to slide within an elongated slot 62 formed in the lower enlarged end of the piston rod Gil. The pin ti serves as a central pivotal connection between a pair of toggle levers 63 and 6 3. The toggle lever M is connected to the footstock frame by means of a stud 65. The other end of the toggle lever 63 is connected by a stud 66 with a slidably mounted hollow sleeve 61 which slides within an aperture 68 within the sleeve 55. The sleeve ii? is held against rotation by means of a pin 69 which is carried by the sleeve 55 and rides within an elongated slot in the sleeve 55. A spring 76 is contained within the sleeve 6'! and is interposed between the end of an aperture of the sleeve iii and a thrust collar H.

When fluid under pressure is admitted through a pipe i2 to a cylinder chamber 13, the piston 59 is moved downwardly and the toggle levers 63 and 64 are moved from the dotted line positions 63a and Ma into the full line positions 63 and 64 (Fig. 3) which serves to move the sleeve 6'! into the position illustrated. This movement serves to com press the spring and, through the connecting parts, moves the sleeve 55 and footstock center 5| into operative supporting engagement with the end of the crankshaft 24. During this movement, fluid is exhausted from a cylinder chamber 74 through a pipe 2 5. The admission to and exhaust of fluid from the footstock operating cylinder 58 will be hereinafter described. This footstock is identical with that shown in the prior United States Patent No. 2,117,960 dated May 17, 1938, to

which reference may be had for details of disclosure not contained herein.

Lapping arm support It is desirable to provide a movable support for a plurality of lapping arms so that they may be simultaneously and quickly moved into an operating or an inoperative position as desired. A pair of spaced arms 8&3, only one of which has been illustrated in the drawings (Fig. 2), are mounted on a rock shaft 8i which is supported in bearings on the rear of the machine base The arms Bil are provided with horizontally extending portions which are connected by two spaced bars 82 and 83 which serve as slide bars or ways for supporting a plurality of lapping arms to be hereinafter described.

The lapping arm assembly supported by the arms 8t is arranged so that it may be automatically moved to and from an operating position to facilitate loading of crankshafts into the machine and removing them therefrom after a lapping operation has been completed. In order to move the entire lapping arm assembly to an inoperative position, a fluid pressure mechanism is provided including a fluid pressure cylinder 8 which is pivotally connected by means of a stud 85 within the base 28 of the machine. A piston 36 is slidably mounted within the cylinder 84 and is connected to one end of a piston rod 87. The other end of the piston rod Si is connected by a stud 98 with an arm pivotally mounted on a shaft 9i] supported within the base iii]. The other end of the arm $39 is connected by a stud iii to one end of a link Q2. The other end of the link 922 is connected by a stud with a toggle lever iii. The adjacent ends of the toggle lever 94 and a toggle t5 are connected by a stud 93. The toggle lever 9 is connected at its other end by means of a stud 96 with the base 2E]. The toggle lever 95 is connected by a stud ill with an arm 98 which is fixedly mounted on the rock shaft ill and is arranged to rock the shaft iii together with the arm 8% and all of the crankpin and bearing lapping arms together with their supporting and actuating mechanisms either into or away from an operating position.

The levers 8t, 92, 9& and 95, as shown in full lines in Fig. 2, are in a position to hold the arm 98 and the arms 80 together with the entire lapping arm assembly in an operating position. After a lapping operation has been completed, fluid under pressure is admitted to the cylinder 8 -3 to cause the piston 86 and piston rod 8? to move toward the right (Fig. 2) to shift the levers 89, 92, 94 and 95 and arm 98 into the dotted line positions 89a, 92a, 94a, 95a. and 93a. This movement serves to rock the arms 80 in a clockwise direction (Fig. 2) to move the entire lapping arm assembly to an inoperative position.

Fluid pressure system A fluid pressure system is provided to control the admission of fluid under pressure to the cylinder 84. A pump 99 within the base 20 of the machine draws fluid through a pipe Hi9 from a reservoir lill within the base 20 and passes fluid under pressure through a pipe M2 to a reverse or control valve M3. The Valve it is of a piston type having a valve stem l lit which is provided at its outer end with a spool-shaped member liiii and is connected by means of a pair of diametrically opposed studs or pins Hi6 mounted on a yoked end of a control lever llil. The control lever [M is pivotally mounted on a stud 18 which is supported by a bracket I09 fixedly supported on the base 20 of the machine.

A plurality of valve pistons IIO, I I I, H2 and H3 are formed integral with the valve stem I04. Fluid under pressure passing through the pipe I02 passes into a Valve chamber H4 located between the valve pistons III and H2 and passes out through a pipe II5 into a cylinder chamber II 6 within the cylinder 84 to cause the piston 86 to move toward the left (Figs. 2 and 3) to shift the lapping arm support arms 80 in a counterclockwise direction (Fig. 2) to position the crankpin and bearing lapping arms in an operating position.

During the admission of fluid under pressure to the cylinder chamber H6, fluid is exhausted from a cylinder chamber I I? at the other end of the cylinder 84, through a pipe II 8, through a valve chamber II9 located between the valve pistons H2 and H3, and out through a pipe I20 into the reservoir IIlI. A fluid pressure relief valve I2I is connected by a pipe I22 with the pressure pipe I02 and serves to by-pass excess fluid under pressure within the pipe I02 to the reservoir NH.

The control valve I03 also serves to control the admission of fluid to the footstock actuating cylinder 58. The pipe I2 is connected to the pipe H5 and serves to convey fluid under pressure to the 'footstock cylinder chamber I3 simultaneously with the passage of fluid under pressure to the cylinder chamber II6 in the cylinder 84. The pipe I5 connects the cylinder chamber I4 of the cylinder 58 with the pipe H8 so that in the position of the control valve I03 (Fig. 3), fluid will exhaust simultaneously from the cylinder chamber 14 in the cylinder 58 and from cylinder chamber II? in the cylinder 84.

When the control valve I03 is shifted into the position illustrated in Fig. 3, fluid under pressure simultaneously enters both the cylinder 58 and the cylinder 04 and due to the fact that less power is required to move the footstock than the lapping arm assembly, the footstock center moves first into an operative position, af r which the lapping arm assembly moves to an operative position adjacent to the crankpins and bearings to be lapped.

Lapping arms In order that all of the crankpins and main bearings on the crankshaft 24 may be simultaneously lapped, a plurality of crankpin and bearing lapping arms .are provided which correspond in number with the crankpins and bearings to be lapped. As illustrated, there are three main bearing lapping arms I30, I3I and I32. There are four crank lapping arms I33, I34, I35 and I36. The main bearing and crankpin lapping arms are supported in spaced relationship with each other so as to simultaneously engage and lap the three main bearings and the four crankpins on the crankshaft 24.

The bearing lapping .arms and crankpin lapping arms are substantially identical in construction. The bearing lapping arms are stationary while lapping the main bearing surfaces which are concentric with the axis of rotation of the crankshaft 24, whereas the crankpin lapping arms are rocked during the lapping operation due to the fact that they engage a crankpin which revolves about the axis of rotation of the crankshaft 24.

A side elevation of the lapping arm I32 is shown in Figs. 2 and 12. The lapping arm I32 as well as all of the other lapping arms are each provided with a pair of pivotally mounted lap supporting arms I40 and MI which are provided at their operative ends with partially cylindrical lap supporting blocks I42 and I43, respectively. The arms I40 and MI are pivotally supported by the studs I44 and I45 on the lapping arm I32. The other ends of the arms I40 and MI are interconnected by means of a pair of toggle levers I46 and I47 which are connected together at their inner ends by means of a stud I 48. The stud I 48 slides in an elongated slot I43 in the side plate of the lapping arm I32. When the toggle levers I46 and I4! are in a straight-line position (Fig. 2), the lap supporting members I42 and I43 are maintained in operative engagement to hold an abrasive or lapping e1ement in operative contact with a portion of the crankshaft 24.

The lapping supporting arms I40 and I 44 are arranged to be automatically moved into .and away from an operative position, and in the preferred construction a hydraulically operated mechanism is provided for actuating the same comprising a fluid pressure cylinder I32a formed integral with the upper end of the lapping arm I 32. A piston I32b is slidably mounted therein and is connected to one end of a piston rod I320. The other end of the piston rod I320 is connected by a stud I50 with a link I5I. The other end of the link ISI is connected to the stud I 48 which pivotally connects the adjacent ends of the toggle levers I46 and I41. It will be readily apparent from the foregoing disclosure that when the piston I321) is moved downwardly, that is, toward the left. (Fig. 2), the piston rod I32c and the connecting link I5! will be moved also in a downward direction toward the left which serves to unlock the toggle levers I46 and I4? and thereby to rock the lap supporting arms I46 and MI together with the lap supporting elements I42 and I43 to an inoperative position out of engagement with the crankshaft 24. When fluid under pressure is passed through a flexible pipe I32d into a cylinder chamber I326, the piston I32?) will be moved upwardly to move the toggle levers I46 and I4! into a straight line position (Figs. 2 and 12) to move the abrasive lapping element into .an operative position in engageinent with the work piece 24 for a lapping operation. Similarly, when fluid under pressure is admitted through a flexible pipe I32f to cause a downward movement of the piston I322) toward the left (Figs. 2, 3 and 12), the toggle levers 46 and 41 will be unlocked to move the lap ping elements to an inoperative position.

It is to be noted in the drawings (Fig, 3) that each of the lapping arms is provided with an independent fluid operated piston and cylinder as well as piston rods which have been designated in the diagram with the same reference numerals as the lapping arm on which it is mounted, the cylinders being designated by the letter a, the pistons by the letter I), the piston rods by the letter 0, and cylinder chambers by the letter e.

It is desirable that all of the lapping elements represented by the supporting members I42 and I43 (Fig. 2) be moved into and away from an operating position simultaneously. This is preferably accomplished by providing a pair of longitudinally extending pipes or manifolds I53 and I54 which are fixedly supported on the spaced arms 80 and serve as a common source of fluid under pressure which may be forced either through the flexible pipe I32d to move the lapping element into an operative position, or when the fluid under pressure is reversed, to flow through the flexible pipe I32) simultaneously to move all of the lapping elements to an inoperative position after the lapping operation has been completed. The admission to and exhaust of fluid from the manifolds or pipes I53 and I54 is controlled by the control valve I03. A pipe I55 is connected between the manifold or pipe I53 and the valve chamber H4 and serves in the position of the valve I33 (Fig. 3) to admit fluid under pressure to the manifold or pipe I53, into the cylinder chamber I326, and simultaneously to all of the other corresponding cylinder chambers in the cylinders on each of the lapping arms to move and hold said lap supporting arms in an operative position for a lapping operation. A pipe I55 is connected between the manifold or pipe I54 and the valve chamber II9 so that in the position of the valve I03 (Fig. 3), fluid may be exhausted from the upper cylinder chambers on each of the lapping arms through the manifold I54 and the valve chamber II9, pipe I23, into the reservoir IIlI.

Each of the lapping arms I30 to I36 inclusive is pivotally supported. The details of the support for the lapping arms being identical, only one support has been illustrated in detail. An arm I65 is pivotally mounted on a supporting member I33 which is clamped in adjusted position on the guide rods 82 and 83. The lower end of the arm I35 is pivotally connected to the supporting member I63 by means of a pivotal connection I61. A pivotal connection I68 serves to connect the arm I55 with the lapping arm r32 50 that the arm I32 is free to move. All of the lapping arms, both crankpin and main bearing arms, are mounted in the same manner so that when the lapping elements are clamped in lapping engagement with a crankpin and main bearing, the crank lapping arms may follow as the crankpin is revolved to produce the desired lapping action.

A flexible abrasive paper or cloth is preferably utilized as an abrading or lapping medium. Each of the lapping arms is provided with a separate strip of continuous abrasive paper which wraps around the crankpin or main bearing and is held in position thereagainst by the lap supporting members I62 and I43. A rod I10 is supported on the rear of each of the supporting members I36 by means of a bracket HI and serves as a support for a reel I12 of flexible abrasive paper I13. The abrasive paper passes through guides I74 and I15 supported on the under side of the supporting member [66 and passes through a series of rollers I13 carried by a bracket H1. The abrasive paper above described wraps around a main bearing or crankpin of the crankshaft 24 and is supported by the lap supporting members I42 and I 33. The worn or used abrasive paper is wound up on a reel I18 which is supported by a stud I19 carried by a bracket I85 supported on the lap supporting arm I 33.

The lap supporting members I42 and I43 are mounted so that they may float or move relative to the arms I40 and MI, so that the lap supporting members I42 and I43 are self-aligning when brought into operative engagement to support the abrasive paper on a crankpin or main bearing for a lapping operation. The brackets III and IBII are fixedly mounted to the floating lap supporting members I42 and I43. A holding pawl IBI cooperating with a ratchet wheel on the end of the reel I18 serves to prevent unreeling of the worn abrasive paper wound up on the reel IIIZ when the lap supporting arms are moved to and from an operating position. As illustrated in the drawings, the abrasive paper is fed manually when desired by the operator by manually turning the reel I18. Only one of the reels I18 and the associated parts to guide the abrasive paper through to the reel H8 have been illustrated in detail. Each lapping arm is provided with similar equipment supported on a separate supporting member IE5. The abrasive paper and wind-up reels for each of the lapping arms are illustrated in the front elevation of the machine, as shown in Fig. l.

The lapping arm I38 is supplied with a strip of abrasive paper I35 which is wound up on a reel I86. The lapping arm I33 is provided with a strip of abrasive paper I35 and the used portion thereof is wound up on a reel I88. The lapping arm I35 is supplied with a strip of abrasive paper I89, the used portion of which is wound up on a reel I35. The lapping arm I3I is supplied with a strip of abrasive paper IBI, the used portion of which is wound up on a reel I92. The arm I35 is supplied with a strip of abrasive paper I93, the used portion of which is wound up on a reel I33. The lapping arm I36 is supplied with a strip of flexible abrasive paper I95, the used portion of which is wound up on a reel I95. Inasmuch as the abrasive paper supporting reels and the guiding means are identical for each of the lapping arms, only one of these mechanisms has been completely illustrated, as shown in Fig. 2.

It is desirable to provide a guiding means for guiding the lapping arms during their swinging movement as they follow the revolving crankpin and to provide a clamping mechanism to clamp all of the lapping arms in their indexed position relative to the supports I55 before the lap supporting members M2 and M3 are released from operative position and the lapping arm assembly swung to an inoperative position to facilitate loading of the machine. It is desirable to provide such a clamping device so that when the arms 85 are moved to an operating position after a new crankshaft has been loaded into the machine, all of the lapping arms will be in the proper indexed position so that the lap supporting members I42 and M3 may be automatically brought into engagement simultaneously with the crankpins and bearings of the crankshaft 24.

In order that the lapping elements may be guided in their swinging movement and held against lateral movement during the reciprocation or oscillation of the crankshaft during the lapping operation, a pair of parallel guiding plates 250 and ZIII are fixedly mounted on the supporting bracket I55 and are spaced apart by a distance equal to the thickness of the lapping arm I32. The lapping arm I32 is guided thereby and is held against lateral movement by the guiding plates 2% and 2%. The lapping arm I is similarly guided by the guiding plates 202 and 253. The lapping arm I33 is guided by guiding plates 2% and 235. The lapping arm. I34 is guided by guiding plates 236 and 201. The lapping arm I3I is guided by guide plates 20B and 2119. The lapping arm I35 is guided by guide plates 2m and 2I I, and the lapping arm I35 is guided by guide plates H2 and 2I3.

Lap arm-clamp device In order to provide means for simultaneously clamping all of the crankpin and bearing lapping arms in their respective index positions, the guide plates 233, 232, 204, 233, 208, 2!!) and 2!2 are each provided with a groove or guideway 2!4 which supports a slidably mounted member 2!5 having cam surface depressions 2!6 formed therein. The guide plate 255 is provided with a pair of cams 2H and 2I8 which engage the cam. shaped depressions 2H3 formed in the slidably mounted member 2!5. It will be readily apparent that if the slide 2 i5 is moved upwardly (Fig. 11) relative to the guiding plate 200, the cam depressions 2H5 engaging the fixed cams 2H and 2&8 will cause the slide member 2!5 to move toward the right (Fig. 11) and thereby bind or clamp the lapping arm H32 in a fixed position relative to the guide plates 255 and 20!. Each of the lapping arms I30 to I35 inclusive is provided with an identical clamping means, consequently only one of these clamps has been illustrated in detail. The guide plates 232, 204, 206, 208, 219 and 2 !2 are each provided with a clamping slide 232a, 234a, 208a, 238a, 213a and 2l2a, respectively.

In order simultaneously to clamp all of the lapping arms, a mechanism is provided for simultaneously actuating the clam ing slides 2l 5, 252a, 234a, 256a, 208a, 2l0a and 2l2a. As illustrated in the drawings, a shaft 22! is rotatably supported in apertures in the guiding plates 200 to 2!2 inclusive. Each of the clamping slides is provided with an elongated slot 222 (Fig. 13). The shaft 22! carries an eccentric 223 which rides within the elongated slot 222. When the shaft 22! is rotated, the eccentric 223 rotating within the elongated slot 222 causes the clamping slide 2E5 to move relative to the guiding plates 2G3 and 20!. The shaft 22! is provided with a plurality of eccentric members corresponding to the eccentric 223, each of which is arranged to engage elongated slots in the respective clamping slides 202a, 204a, 206a, 208a, 2l8a and 2|2a.

Clamp actuating motor A vane type fluid pressure motor 230 is provided for rocking the shaft 22! to clamp and release the lapping arms. The motor 233 is provided with a rotor shaft 23! which supports a rotary vane 232. The rotor shaft 23! projects from the motor casing toward the left (Fig. 11). An arm 233 is supported on one end of the rotor shaft 23!. The arm 233 is provided with an enlarged head 234 having a notch 235 formed in the outer end thereof. A lever 236 is fixedly mounted on the shaft 22! and is provided with a spring-pressed plunger 23'! which is arranged to engage the notch 235 to lock the lever 235 to the lever 233 so that the rotation of the vane 232 of the motor 235 will be transmitted to rotate the shaft 22! to clamp or release the lapping arms. The plunger 23? is connected with a knob 238 by means of which the plunger 23] may be withdrawn from. the notch 235 so that the clamping mechanism may be operated manually, if desired.

In order to attain one object of the invention, it is desirable to provide suitable interlocks so that the various mechanisms of the machine will operate in a predetermined sequence. When a crankshaft has been loaded into the machine, the control lever i3"! is moved to shift the control valve 33 and start the cycle of operation. It is desirable that the various mechanisms should operate in the following sequence:

(a) Footstock center 5! moves in to grip the work.

(1)) Arms 80 which support the crankpin and bearing lapping arms swing forward into an operating position.

(0) Jaws close onto work.

(d) Lapping arms unclamped.

(e) Headstock starts rotation, allowing work to rotate a predetermined number of rotations.

(f) Headstock stops rotation.

(g) Lapping arms are clamped in an indexed position.

( Jaws open.

(i)Arms 8!! swing back to inoperative position.

(3) Footstock center 5! moves out of engagement with work to release the same, after which the crankshaft may be unloaded from the machine.

Interloclcs The ports in the valve "33 are so arranged that fluid under pressure will be admitted to the various hydraulic cylinders in the sequence above enumerated. It is, however, desirable that the various mechanisms have sufficient time to function before the next mechanism operates. It is, therefore, desirable to provide an interlocking of the various mechanisms which may comprise a series of stops which serve to limit the movement of the control valve when it is moved in either direction. These stops are interconnected with the various mechanisms so that after a mechanism has performed its function, the valve stop will be automatically withdrawn, thereby permitting a further movement of the control valve !03.

A stop collar 248 is fixedly mounted on the rear end of the valve stem !04. The collar 24B is arranged to slide within an aperture within a casing 249 mounted on the rear end of the casing of the valve I33. The casing 249 serves as a support for a plurality of spring-pressed stops which are arranged intermittently to stop the movement of the valve stem I04 when it is moved either towards the rear after a lapping operation has been completed or when the valve is moved forward after a new crankshaft has been loaded into the machine to start a lapping operation. As shown in Fig. 3, the valve I53 together with the other mechanisms of the machine are shown in the position during the lapping operation.

When the valve stem N34 is in the forward position (Fig. 3), a stop pawl 250 serves to prevent shifting the valve toward the rear to stop the lapping operation. The stop plunger 25!] is connected by a link 25! to one arm of a bell crank lever 252 which in turn is connected by a flexible cable commonly known as a Bowden wire 253 with one arm of a bell crank lever 254. The bell crank lever 254 is mounted on the outer end of a clutch operating shaft 255 on the headstock 22 which is connected to move a clutch 253 into or out of engagement to start the headstock rotation. As shown in the drawings (Figs. 3 and 10) the headstock clutch is engaged and the crankshaft is being lapped. This lapping operation continues until a counting mechanism contained within the headstock 22 above referred to automatically stops the headstock after the crankshaft has been rotated a predetermined number of rotations for a lapping operation. When the clutch 256 is disengaged to stop the headstock rotation, the shaft 255 and bell crank 254 are rocked in a clockwise direction and this movement serves to pull on the flexible cable 253 to rock the bell crank 252 in a counterclockwise direction and thereby automatically withdraw the stop plunger 250 from the path of the stop collar 248. During the lapping operation when the headstock is running, the stop plunger 25! prevents accidental shifting of the valve towards the rear and holds it locked in a forward operating position.

The valve stem tilt may then be shifted until the stop collar 2 38 engages a stop plunger 26! which is arranged in a manner to be hereinafter described to prevent further rearward movement of the valve until the lapping arms are clamped in position. The spring-pressed stop plunger 2% is connected by a link 265 with one arm of a bell crank lever 262, the other arm of which is connected to a flexible cable or Bowden wire 263. A spring 264 normally tends to move the bell crank in a clockwise direction. The Bowden wire or flexible cable 263 is wound partially around the periphery of a disk 2% which is mounted on the end of the shaft 22! and is connected by means of a screw 265 with the periphery of the disk 2% (Fig. 11). The valve stem I04 cannot be moved further toward its rearward position until fluid under pressure admitted through a pipe 305 actuates the clamping motor 230 and thereby clamps the lapping arms in an indexed position. The motor 23c rotates in a clockwise direction (Fig. 3) to clamp the lapping arms and this movement also rotates the shaft 22E and the disk 266 also in a clockwise direction which serves to pull the flexible cable or Bowden wire 263 toward the left (Fig. 3), thus rocking the bell crank lever 252 in a counterclockwise direction which serves automatically to withdraw the stop plunger 265) out of the path of the stop collar 248.

The valve stem 584 may then be moved rearwardly until it is again stopped by the stop collar 2% engaging the stop plunger 21%. The plunger 2% is connected by a link chain 27! with one arm of a bell crank lever 212, the other arm of which is connected to a flexible cable or Bowden wire 273. The other end of the Bowden wire or cable 213 is connected to the stud M8 which connects the toggle levers I46 and M! with the hydraulic actuating mechanism. The valve stem we cannot be moved further to the rear until fluid under pressure admitted through the pipe l56 into the manifold or pipe 854 causes a downward movement of all of the pistons I301), i331), i361), I351), I351), i361) and l32b to actuate the toggle levers and open the lamp supporting arms or jaws. The downward movement of all of these pistons serves through the Bowden wire 2173 to rock the bell crank lever 212 in a clockwise direction (Fig. 3) which in turn, through the link chain 2H, automatically withdraws the stop plunger 2% from the path of the stop collar 248.

After the plunger 27!! has been withdrawn from the path of the stop collar 248, the valve stem we may then be shifted into its extreme rearward position, namely that shown in Fig. 6, so as to admit fluid under pressure through the pipe l l 8 into the cylinder chamber ill of the cylinder 84 to rock the arms 8% so as to simultaneously withdraw the entire lapping arm assembly to an inoperative position. At the same time the arms 89 withdraw the lapping arm assembly to an inoperative position, fluid under pressure is admitted through the pipe it to actuate the piston 59 and withdraw the footstock center M. In this position of the parts, the crankshaft which has just been lapped may be removed from the machine.

After a new shaft has been inserted in the machine, the lever It! in then moved in a clockwise direction (Fig. 2) to cause a forward movement of the valve, that is, toward the left (Fig. 7) The valve stem IE4 can be moved until the stop collar 2% engages a stop plunger 280 which prevents further forward movement of the valve. This forward movement of the valve is sufficient to uncover the port and admit fluid under pressure through the pipe I I5 into the cylinder cham ber N6 of the cylinder 84 to cause the arms 8!] supporting the lapping arm assembly to move to an operating position. The stop plunger 280 is connected by a link chain 28| with a bracket 282 which is fixed to the lever 95. When the lever 95 is moved into the position illustrated in Fig. 2, the stop plunger 230 is moved downwardly (Fig. 3), thus permitting a further forward movement of the valve stem l 94 until the stop collar 248 engages a stop plunger 389. The stop plunger 30!! is connected by a link 30! with a bell crank lever 3&2 which is also connected to the Bowden wire or flexible cable 213.

The movement of the valve stop collar 2% into engagement with the stop plunger 30!! serves to uncover a port so as to admit fluid under pressure through the pipe H55 to manifold or pipe E53 and thereby admit fluid under pressure to the lapping arm cylinders to close the lap supporting arms or jaws into operating engagement with the work. This closing movement causes the pin M8 to move upwardly (Fig. 3) into the position illustrated therein which serves through the Bowden wire 213 to rock the bell crank lever 3132 in a counterclockwise direction automatically to withdraw the stop plunger 3% out of the path of the stop collar 248, thus permitting the valve stem IM to be moved further in a forward direction, that is, toward the left (Fig. 3) until it uncovers a port to admit fluid under pressure through the pipe 394 to actuate the lapping arm clamping motor 23!) to unclamp the lapping arms. This movement rotates the shaft 22! and the disk 26% in a counterclockwise direction which serves through a Bowden wire or flexible cable 3!!! to rock a lever 3M which is pivotally mounted on a stud M2 on the headstock in a clockwise di rection into the position illustrated in Fig. 3, thus shifting the lever 3H out of the path of a projection 353 on the bell crank lever 25 i, which renders the headstock operative. In this position of the parts, the headstock control lever 320 may then be rocked to start the rotation of the headstock and the crankshaft 24 to be lapped. The lapping operation continues until the counting mechanism within the headstock, after a predetermined number of rotations of the crankshaft, again stops the rotation thereof, after which the cycle of operation of the valve and its interlocking plungers is again repeated.

After the headstock has been stopped by shifting of the clutch, the bell crank lever 254 rocks in a clockwise direction (Fig. and when the hydraulic motor 239 is actuated to rotate the shaft 226 and the disk 266 to clamp all of the lapping arms in an indexed position, the Bowden wire or flexible cable 3H3 is pulled to rock the lever 3H in a counterclockwise direction, that is, downwardly, as shown in Fig. 3, until a portion of the lever 3H lies in the path of the end 3! 3 of the bell crank lever 25d so as to prevent startthe headstock rotation when the lapping arms are in a clamped position. It will thus be seen that by providing a plurality of stop plungers to cause a restricted movement of the valve stem I 84 both on its rearward and forward movements, all of the various mechanisms of the machine are interlocked so that they must all be actuated in a definite and predetermined sequence.

When the valve I03 is in the position illustrated in Fig. 3, fluid under pressure entering through the pipe H32 enters a valve chamber I I i between the valve pistons III and H2 and may pass through the pipes H5, I55 and 364 to the various mechanisms of the machine. In this position of the valve, fluid may exhaust from the other side of the various fluid cylinders through the pipes H8, 555 and 3%, into the valve chamber H9 located between the valve pistons I I2 and H3 and pass out through the exhaust pipe I29 to the reservoir IIlI. Similarly, when the valve is shifted into its other extreme position (Fig. 6), fluid under pressure passing through the pipe Hi2 enters the valve chamber I M located between the pipes H8, 5555 and 385. At the same time, fluid may exhaust through the pipes H5, H55 and 394 through a valve chamber 32!! and out through an exhaust pipe 32I which connects with the pipe I2!) to return the exhaust fluid to the reservoir IIJI.

The operation of this improved machine will be readily apparent from the foregoing disclosure. A work piece. such as a crankshaft 24, to be lapped is laid in position on a cradle 33!) which is supported on the table 2I between the head 22 and footstock 23, and the flange on the crankshaft is positioned. with the aligning hole in engagement with a drive pin on the headstock. In this position of the valve, the valve stem I04 is in its rearward position. The control lever I01 is then moved in a clockwise direction to move the valve stem toward the left (Figs. 2 and 3), which movement operates first to admit fluid under pressure through the pipe H5 and pipe 12 to move the footstock center 5| into supporting engagement with the end of the work piece. At the same time, fluid passing through the pipe I I5 enters the cylinder chamber IIB to cause a downward movement of the piston 86 (Fig. 2) to move the toggle levers 94 and 95 from their dotted line position into the full line position (Fig. 2) to rock the arms 80 and the entire lapping arm assembly into an operating position, which movement withdraws the stop plunger 280 and permits further movement of the valve. The lever I 01 is moved to a further extent and fluid under pressure is admitted through the pipe I55 to the manifold or pipe I53 which conveys fluid to all of the lapping arm cylinders to actuate the toggle levers on each arm and thereby to swing the lap supporting arms or jaws into an operating position to hold the lapping element, namely the strips of abrasive paper, in lapping engagement with all of the crankpins and bearings of the shaft. This movement serves through the Bowden wire or cable 2'53 to rock the bell crank lever 39?. in a counterclockwise direction to withdraw the stop plunger 3%, thus permitting a further movement of the valve stem HM toward the left (Fig. 3). The continued movement of the valve serves to open a port and admit fluid under pressure through the pipe 3% to the lapping arm clamp motor 235 which rotates the shaft HI and the disk 2% to unclarnp the lapping arms. Rotation of the disk 25% in a counterclockwise direction serves through the Bowden wire or flexible cable am to rock the lever 3 in a counterclockwise direction so that it is out of the path of the projection 3I3 of the bell crank lever 254 which renders the headstock mechanism operative and by manual shifting of the lever 320, the headstock may be set in rotation to start the lapping operation on all of the crankpins and main bearings. The lapping operation continues for a definite number of rotations of the shaft, after which a counting mechanism within the headstock 22 automatically disengages the head stock clutch 256.

During the lapping operation, the stop plunger 25% is in an operative position so as to prevent accidental shifting of the valve I0 toward the right (Fig. 3). When the headstock is automatically stopped by the counting mechanism, the bell crank lever 254 (Fig. 3) is rocked in a clockwise direction which serves to rock the bell crank lever 252 in a counterclockwise direction and thus withdraw the stop plunger 250 so that the valve stem I94 may be moved toward the rear or toward the right (Fig. 3). The lever I01 may then be moved in a counterclockwise direction to move the valve stem I04 toward the right (Fig. 3), which movement continues until the stop collar 248 engages the stop plunger 260. During this movement, the valve shifts so as to admit fluid under pressure through the pipe 305 to the lapping arm clamp motor 23!] to rotate the shaft 22I in a clockwise direction to clamp all of the lapping arms in an indexed position.

This movement serves to pull the Bowden wire I' or flexible cable 3|!) to cause a counterclockwise movement of the lever 3 to swing downwardly into the path of the projection 3I3 of the bell crank 254 and thus lock the headstock so as to prevent starting work rotation while all of the lapping arms are clamped in an index position.

At the same time, the rotation of the disk 2'65 in a clockwise direction pulls the Bowden wire or cable 263 to move the bell crank 262 in a counterclockwise direction and thereby withdraw the stop plunger 250, thus permitting a further rearward movement of the valve stem IN. The valve stem IM may then be moved until the stop collar 243 engages the stop plunger 2W which serves to open a port so as to admit fluid under pressure through the pipe I56 into the manifold or pipe I5 3 which causes a downward movement of all of the pistons within the lapping arm. cylinders to actuate all of the toggle levers and to open the lap supporting members or jaws. During the opening of the lap supporting members or jaws, the cable 273 is pulled to rock the hell crank lever 212 in a clockwise direction (Fig. 3) to withdraw the stop plunger 27$], thus permitting the valve stem I84 to be moved into its extreme rearward position. This movement of the valve stem serves to open a port so as to admit fluid under pressure through the pipe H8 into cylinder chamber III of the cylinder 84 to cause the arms to swing the entire lapping arm assembly to an inoperative position, after which the crankshaft which has been lapped may be removed from the machine.

It will thus be seen that there has been provided by this invention apparatus in which the various objects hereinabove set forth together with many thoroughly practical advantages are successfully achieved. As many possible embodiments may be made of the above invention and as many changes might be made in the embodiment above set forth, it is to be understood that all matter hereinbefore set forth or shown in the accompanying drawings is to be interpreted as illustrative and not in a limiting sense.

I claim:

1. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a clamping mechanism for clamping said arms relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected toactuate said footstock, said frame, said lapping arms and said clamping mechanism, a single manually operable control valve to control the admission to and exhaust of fluid from all of said motors, and a stop device to hold said control valve in an operating position during rotation of the headstock.

2. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a clamping mechanism for clamping said arms in an indexed position relative to said frame, a rotatable work support including a motor driven headstock and a footstock rotatably to support a crankshaft therebetween, a clutch mechanism to start said headstock, a plurality of fluid pressure actuated motors respectively connected to actuate said footstock, said frame, said lapping arms and said clamping mechanism, a manually operable control valve operatively connected to control the admission to and exhaust of fluid from all of said motors, a stop to hold said control valve in an operative position during rotation of the headstock, and an automatically actuated mechanism to withdraw said stop when said headstock clutch is disengaged after completion of a lapping operation.

3. 'In a lapping machine having a plurality of lapping arms, a movable frame to support all of said arms, a clamping mechanism for clamping said lapping arms in an indexed position relative to said frame, a rotatable work support including a motor driven headstock and a footstock rotatably to support a crankshaft to be lapped, a plurality of fluid pressure actuated motors respectively connected to said footstock, said frame, said lapping arms and said clamping mechanism, a manually operable control valve operatively connected to control the admission to and exhaust of fluid under pressure from all of said motors, a spring pressed stop to hold said control valve in an operative position during rotation of said headstock, and connections between said clutch and said stop whereby said stop is automatically withdrawn when the clutch is moved to stop rotation of the headstock.

4. In a lapping machine having a plurality of lapping arms, a movable frame to support said lapping arms, a clamping mechanism to clamp said lapping arms relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected to said footstock, said frame and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, and an interlock between said headstock clutch and said lapping arm clamping mechanism which serves to prevent starting said headstock when the lapping arms are clamped.

5. In a lapping machine having a plurality of lapping arms, a movable frame to support said lapping arms, a clamping mechanism to clamp said lapping arms relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock,

. a plurality of fluid motors respectively connected to said footstock, said frame and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, an interlock between said head stock clutch and said lapping arm clamping mechanism which serves to prevent starting said headstock when the lapping arms are clamped, and a stop to limit the movement of said control valve to prevent movement of said valve during the rotation of said headstock.

6. In a lapping machine having a plurality of lapping arms, a movable frame or carrier to support said arms, a clamping mechanism for clamping said arms in an indexed position relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected to actuate said rootstock, said frame, said clamping mechanism and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, a stop to limit the movement of said valve in one direction, and automatically actuated mechanism actuated by releasing the lapping arms from the work to withdraw said stop so as to facilitate movement of said valve to its rearward position to admit fluid under pressure to the frame motor and move the frame and lapping arm supported thereby to an inoperative position.

'7. In a lapping machine having a plurality of lapping arms, a movable frame or carrier to support said arms, a clamping mechanism for clamping said lapping arms in an indexed position relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected to actuate said footstock, said frame, said clamping mechanism and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, a stop to limit the rearward movement of said valve during the lapping operation, means actuated by the stop ping of said headstock automatically to withdraw said stop, a second stop to limit said control valve which serves to prevent movement of the valve to withdraw said frame until the lapping arms have been released from the work, and automatically actuated mechanism actuated by releasing the lapping arms from the work to withdraw said stop so as to facilitate movement of said valve to its rearward position to admit fluid under pressure to the frame motor to move the frame and the lapping arms supported thereby to an inoperative position.

8. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a rotatable work support including a clutch controlled headstock and a footstock, a plurality of fluid motors respectively connected to said rootstock, said lapping arms, and said frame, a manually operable control valve to control the admission to and exhaust of fluid from said motors, and a stop to limit the movement of the control valve in one direction so as to prevent admission of fluid to actuate the lapping arms until the frame is in an operative position.

9. In a lapping machine having a plurality of lapping arms, a movable frame or carrier to support said arms, a rotatable work support including a motor driven headstock and a footstock, a plurality of fluid motors respectively connected to said headstock, said frame and said lapping arms, 7

a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, a stop to limit themovement of the control valve in one direction to prevent the admission of fluid to actuate said rapping arms until the frame is in an operative position, and means automatically actuated by movement of said frame into an operating position to withdraw said stop and thereby facilitate further movement of the control valve.

10. In a lapping machine having a plurality of lapping arms, a movable frame to support said arms, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected to said footstock, said frame and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, a movable stop to prevent engagement of the headstock clutch to r0- tate the work until the lapping arms are in operative engagement with said work, and automatically actuated means actuated by movement of said lapping arms into operative engagement with the work to withdraw said stop so as to facilitate starting of the lapping operation by engagement of the headstock clutch.

11. In a lapping machine having a plurality of lapping arms, a movable frame or carrier to support said arms, a clamping mechanism to clamp said arms in an indexed position relative to said frame, a rotatable work support including a motor driven headstock and a footstock, means including a manually operable clutch to start said headstock, a plurality of fluid motors respectively connected to said footstock, said frame, said clamping mechanism and said lapping arms, a manually operable control valve to control the admission to and exhaust of fluid from all of said motors, a stop to limit the movement of said control valve in one direction until the admission of fluid to said frame motor moves the frame and lapping arms carried thereby into an operative position, means actuated automatically by said frame when it is moved into an operating position to withdraw said stop, a second stop to limit the forward movement of said valve during admission of fluid to said lap arm motors to close said laps on a shaft to be lapped, means actuated automatically by closing of said laps automatically to withdraw said second stop to facilitate a further movement of said control valve to admit fluid under pressure to said lap motor to unclamp said arms, an interlock between said clamp mechanism and said headstock clutch including a stop to prevent engagement of said clutch until actuation of the clamping mechanism to unclamp the lapping arms, and means actuated automatically by said clamping mechanism to withdraw said third stop, thereby rendering said headstock operative to facilitate manual actuation of the headstock clutch to start the lapping operation.

12. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during rotation of the headstock and means automatically actuated by disengagement of the headstock clutch to withdraw said stop to facilitate movement of the control valve.

13. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during rotation of the headstock and connections between said headstock clutch and said stop whereby the stop is moved automatically to an inoperative position when the clutch is disengaged.

14. In a lapping machine as claimed claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during actuation of the clamping mechanism and means automatically actuated by said clamping mechanism to withdraw said stop to facilitate further movement of the control valve.

15. In a lapping machine of the type set forth in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during actuation of the lapping arm clamping mechanism and connections between said c1amping mechanism and said stop automatically to withdraw said stop to an inoperative position when the clamping mechanism is actuated to clamp the lapping arms so as to facilitate a further movement of the control valve.

16. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during opening of said lapping arms and means automatically actuated by the opening of said lapping arms to withdraw said stop to facilitate further movement of the control valve.

17. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during the opening of said lapping arms and connections between said lapping arm actuating mechanism and said stop automatically to withdraw said stop to an inoperative position when the lapping arms are opened after a lapping operation has been completed to facilitate a further movement of the control valve.

18. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during movement of the frame and lapping arm assembly to an operative position, and means automatically actuated by movement of said frame to an operative position automatically to withdraw said stop to facilitate a further movement of the control valve.

19. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a stop to limit the movement of the control valve in one direction during the movement of the frame and lapping arm assembly into an operative position, and connections including a link chain connected between said frame and said stop automatically to withdraw said stop to an inoperative position when the frame and lapping arm assembly are moved into an operative position to facilitate a further movement of the control valve.

20. In a lapping machine as claimed in claim 1, the combination with the parts and features therein specified, of a control valve, a stop to limit the movement of the control valve in one direction during closing of the lapping arm jaws to prevent unclamping the lapping arms and starting of the headstock, and connections between the lapping arm jaws and said stop automatically to withdraw said stop to facilitate a further movement of the control valve.

WALLACE I-I. WOOD. 

